If you’re sitting for the ARRT Radiography Exam in the near future, you may want to make sure you understand dose-response curves. It’s a topic that typically trips up our users and you’re likely to come across one on the ARRT Radiography Exam. We’ve partnered with Dr. Roger Seheault from MedCram.com to help us break it down for our users via video in less than two minutes. Before you watch the video explanation, try answering the practice question below. Good Luck!
Radiation and Dose Response Curve Practice Question
Question: Which of the following dose-response curves represents a linear threshold response to radiation?
- C (Correct)
- B and C
- A and C
Correct answer: (B) Curve C.
Curve A is a linear curve but its position on the x-axis shows it is a nonthreshold dose-response curve. It represents an ambient dose of radiation from the background and cosmic radiation.
Curve B is a linear nonthreshold dose-response curve, representing the response of humans to the late effects of ionizing radiation. Theoretically, Curve B represents a linear nonresponse threshold that could cause a response to one x-ray photon.
Curve C is a linear dose-response curve that shows a certain dose of radiation (threshold dose) must occur before a response will occur.
Curve D is a nonlinear threshold curve, which reflects a change in response rate with increasing doses of radiation after the threshold dose is given.
Reference: Bushong, S. C. (2013). Radiologic science for Technologists: Physics, biology, and protection (10th ed.). St. Louis, MO: Elsevier.
How did you do?
Whether you answered the question correctly or not on your first try, you should now have a better understanding of how to answer dose-response curve questions. Be sure to avoid any surprises on exam day. Check out our blog post on Five Things to Know About the ARRT Radiography Exam.
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